1. Field of the Invention
The present invention concerns a lateral guidance device for a ski boot, whose front end is attached to a ski, such as a cross-country ski, and whose heel is free to move at least vertically.
2. Description of Background and Other Information
Various devices are already known which assure the lateral guidance of a cross-country ski boot in relation to the ski on which it is mounted. Some of these devices use a lateral guidance rib which is mounted on the upper surface of the ski, or which is integral with it, this rib cooperating with a longitudinal groove of a complementary shape provided in the sole of the cross-country ski boot, in order to assure the lateral guidance of the boot when skiing cross country.
Such lateral guidance ribs are usually embodied on a mounted small plate, generally of a plastic material, which is attached to the upper surface of the ski. Then, these guidance ribs, at least as far as their front part is concerned, are subjected during skiing to significant stress imposed by the front part of the boot. Accordingly the ribs must be made of materials which are very light and very firm, which increases their fabrication costs.
Also, it is extremely difficult to mold such perfectly flat guidance ribs, because of their relatively long length and the differences in height between the rib and its small support plate, which render them particularly sensitive to deformation and retraction. This is why, most of the time, one is constrained to adjoin to a classic screw binding system an adhesive binding intended to apply the base surface of the plates to hold the guidance ribs on the upper surface of the ski. Yet such a gluing operation represents an additional step in production of the product and is thus likely to increase its cost.
In addition, in the case of such a binding on the upper surface of the ski, the addition of a small plate provided with a guidance rib increases the rigidity of the latter and adds to the original rigidity of the ski, thus increasing it by given value. Therefore, less rigidity of the rib is more important.
When skiing, another problem is bending of the ski, which requires a longitudinal displacement of the rib in relation to the binding system.